If you have not studied Latin before, the place to start is Latin 1 in either the Fall or the Winter term, followed by Latin 2 in the Winter or Spring and then Latin 3 in the Spring or Fall. In these courses, you learn by doing. You'll begin with very simple picture-sentence combinations and progress rapidly to reading short narratives in Latin that gradually build up your vocabulary and your understanding of how Latin sentence structure is different from English. Along the way, you'll also have some opportunities to study images, floor plans, and bits of history that bring the Roman empire to life.
If you have already read some Latin literature before coming to Dartmouth (for instance, an AP course in high school), you will probably want to start with Latin 15 (Literature and the Romans), which is offered every Fall. Latin 15 introduces you to essential elements of Roman literary culture and its academic study today: questions of literacy, book production, conceptions of literary achievement, textual transmission, and the relationship between antiquity and modernity. You also become familiar with library resources, including materials for reading Latin inscriptions and illuminated manuscripts in Dartmouth's collection.
For students who have studied some Latin but are not quite ready for Latin 15, there is also Latin 10 (Reading Latin Texts), which is usually offered in the Winter term. Latin 10 introduces the skills that are needed for reading unadapted texts in Latin, including short selections from Catullus, Virgil, Pliny, and other authors. Both Latin 10 and Latin 15 also include some review of grammar as appropriate to your level.
To determine what Latin class is best for you, please read About Placement in Latin Classes. To learn about satisfying the Language Requirement for graduation, please read About Satisfying the Language Requirement with Latin.